I fail to understand why people who buy computers think that all you need to do is turn them on, use them and do absolutely nothing else to ensure it continues to work properly. Regular maintenance is a necessary task for anything you own... including a computer! That is, of course, unless you have lots of disposable income in order to go out and purchase another one when yours "crashes and burns."
Just like any other product (lawn-mower, air-conditioner, fax-printer... or your vehicle for example), all are in need some sort of maintenance in order to work efficiently. They need to be cleaned (physically) to ensure all parts function properly. They may need fluids like gasoline, oil, air-filters, ect. I'm sure you get the picture. However, many people don't think about things like this when it comes to their own personal computers!
You simply can't turn on a computer day-after-day and expect it to work as efficiently as it did when you first acquired it if you do nothing at all to maintain or service it. The thing is, the major tasks needed to internally maintain a computer can be scheduled to run regularly, without any effort on behalf of the user. Nowadays things like defragging, updating, scanning and such can be scheduled to run within any OS (operating system). Years ago it was necessary for the user to manually run these types of system maintenance tasks. But today, you simply need to schedule the tasks to run automatically. So, what's the problem you may ask? Who knows... Maybe the user is nervous about clicking the wrong buttons and messing the computer up. Or perhaps he/she doesn't know how to go about setting up the automatic tasks... Your guess is as good as mine. However, anyone who owns a computer should treat it like any other product they own. Read the manual; familiarize yourself with its parts/installation/operation, troubleshoot problems, ask questions... Find the answers and GET 'ER DONE!
As for physically cleaning a computer... Of course, this chore would require hands-on application. From time-to-time a computer could use a physical internal cleaning (although I wouldn't open it up and vacuum it out like I've heard some people do). This can be done by a computer technician at any computer repair/service outlet. But, if wiping down your computer to eliminate dust accumulation (especially around the air-circulation filters/fans) is too laborious a chore, then you have a problem. This is the simplest task to maintain it physically. In addition, keeping the room the computer is located in free of dust and other air-borne bi-products (nicotine residue in particular) will significantly reduce the need for internal cleansing.
Albeit I am an not an expert on computers, I have been working with them since they first arrived on the world scene... far before they were available (or affordable) to the general public. The first thing I decided was to discover all I could about computers; their capabilities, limitations and such. From then on, it was a matter of trial and error in regards to understanding software applications, hardware installations, programs, system maintenance, ect, ect. But everyday was a learning process. And it still is today. Computers and their applications are constantly evolving. What is new today, quickly becomes old... and you will need to UPDATE to keep "in the know."
So, that's what I continue to do -- listen, watch, learn and apply. In the meantime, I use the knowledge I've attained to maintain what I have in the manner required. It doesn't matter whether it's my computer, vehicle, A/C, lawn equipment - I intend to get the most out of the products I purchase. And, if that means maintaining them correctly, that's exactly what I will do.